Vactjtim kesponsive device



July 5,- 1932.

F. B. wEsT ET' AL VACUUM RESPONSIVE DEVICE Filed oct. 1o. 192e .peso

Patented July 5, y193.2 i.

me w.' um hb,

c www@ www@ 6 connection withrinternal combustion engines v aterth engine'is'stopped: i" When theengine isf-f1`lsecl'` forpropellm@ n'irotor vehiclesifly the switehfis generailyflooatedfonthe dashboard;

ybumveni-th'ouglr italie conveniently situated '19 fr Y*theldriver t .-is," nevertheless; 2' frequently v lili 'v y 1,1 #111. 1'1 Vff :,115

t flel'object'of the present invention is to provide 'a switch.. whereby the electricalrcurf rent eabeeswtehedfonfindoi and-a1 means ferautematicallyfopcwtingit in Suche mani nerthatlthevelectricalcircuitiis-lclosedfonly whilst thee'nginei's rnnningand for a limited tiefafterthefengine-has stoppedhecircuit tlienibeing opened andy remaining 'open Suntil the engineiisagain simi-,ediv if. y

i experimentsfhave demonstrated .that-thisfobject may beachievedrbymtiizing i the 'suction strokesl o'fthefengine t create a partialvacuum Jini a' suitabiyf-lsliaped ifvessiel provided withi'diaphmgm arranged so that the y.periph@railf; midgets/fixed whilst-the centmfporticn is: freno xncwein: afdimcticn" at rghtlangles' t to :thehplane thereoLf-aihinged 'switch orccntact armb'ein'fg connected to-the dilphfragmso that thef'movement orthelatter willie n and closgthe ig'nition'circnitpand inserting-1a leaky: ci escapevalvc" in thefpipe` line between the engine manifold intakieand the vacuum chamber, or in thechamber `itself, so that (the vacuum fcreatedwill temporarf i' v" ffrflfk-Fi if* Hf: LI if .151x

`; :accompanying drawing :'-.-y

l The .figure iisza centred sectionallelevation showing ionezemethod yb which? ounvention ma becarriedinteyeifyeet f .rgccording to-:thefconstruction yshown in the drawing, armetaijvauumehamber lisxed e tolanyypartthe ychassisnrany-ether con'- lvenent; fixture yin any appropriate mannen Land/*iisgprovided with a central-aperture 1 1 f thrqnghwhich' it; is eOnnectedby-fa pipe :1 1er to 'the engine Inismifold intake. lle:Seated upon Y'thaitopnirthe #vacuum 'chamber'v is f a dscl lwhichlmayybe made of thin vslieetf,eell.n1oidfor metaliorit mayr be fof zg, serial no. 311,685,

and 1n 11s-traue yAugust 1a, 192s;

leather ofpia suitable-xthicknessfsiichddiaphragm 12; being snrinountedby a'fdisc 414;` preferably offbre. A bolt `l3fis .passed-'fu V-' Wardlyth'rough a'central aperture inthe aphragm 1 12Which-L is secured toI 5` the f undertight joint: The bolt lalso passes 'through a' centralik aperture 'inthe :libre disc lfifand theneethrough vanother f aperture incthecen:

is,securedtotheiibre'disclllby'thebolts 16 f E andfniits 16m, the heads of thefboltf'lbeing countersunkdn order vthat theyy will; lifel Hush withV thefunderside of the 'disc :14. The pe ripheral edgesy of] the discs l2 -and 1li-efe clamped tightly in position'upon the chain@ ber -10byv meansr of `a flanged ring 17 *which isinternally fscrewthreaded (18)*to enga-ge with an external scre berllw- The disc., 14 serv w thread 19 on thecham-f esA as an insulating me,-

diumto insulate the'U shaped -jswitch cafrryfing frame 15, Whilst it :also protects the --dia pliragm 12 againstfany possibility of lbeing danniged-` by back` pressure; caused;` by' back fire. The upper end of one ofthe side members ofthe-'frame 1-5h`as ya Contact carrying :1r-m12() hinged thereto atf21, theothersid'e member being provided `with aaterminal 22 that isfsecured tov a `block, of electrical IkOnL conducting material 23 which is :secured-@to the Valf-renie vlbythe screw 24.-f,--The-sidelmeni hereof/the frame lfvvhich'carries thev Contact carrying Iar-rn 2() is r also: provided with 4; l'a terminal-@Qwhich isf screwed directly f into the-.sidermember:, The terminalsf22land 25 are-forthe purpose of enabling the switch fraineto beinsertedf-in the ignition circuit,

a-leadwirej S26-from the electric battery being: connected *to one of lthe `4terminale22 Whilstthe other lead 26a connectsthe `high other end of' which is connected by any suit-l able means to the adjacent side member of the frame 15. The spring 31 being held in tension between the side member of the frame i 15 and the extension 20a the hinged arm is normally held in a raised position, its upper face then abutting against the underside of the nut 29. In this position a space will eX- ist between the contact pieces 27 and 28 and the electrical circuit will therefore be open.

In operation each suction stroke ofthe engine will create a partial vacuum in the chamber 10 thereby causing the diaphragm 12 to belly downwardly and in doing so it will carry with it the bolt-13 and hinged arm 20 thereby bringing the contact pieces 27 and 28 together and closing the electrical ignition circuit. When the engine is stopped the pressure within the chamber 10 will return to normal or atmospheric pressure and the diaphragm will be permitted to return to its normal iiatshape, the spring 31 assistingl such return by raising the hinged arm 20, nuts 29 and 30 and the bolt 13 to which the nuts are attached. f

The switch frame 15 is enclosed within a removable metal cover 32 which lits neatly over the flanged ring 17 and may be secured in position by set screws 33, or any other suitable means. The cover 32 will be provided with an aperture 32a through which the leads 26 and 26a may pass.

The appliance as above described has been foundpto give excellent results for general purposes, but when the speed of the engine is reduced below a certain point there is a f tendency for the contact arm 20kto chatter.

This is overcome by inserting a'leaky or escape valve, preferably of the ball type,in

the pipe line 11a or it may be located within the chamber 10, as shown inthe drawingin order totemporarily maintain the partial vacuum within the chamber and thus prevent the contact arm 20'from being actuated by its spring 31 in the interval between the suction strokes of the pistons of the engine,

` the partial `vacuum causing the contacts 27 and 28 to be held together and thus maintain a closed circuit through the leads 26 and 26a as hereinbefore described.

i The escape valve as shown in the' drawing consists of a body part 34 lhaving at one end thereof'a short cylindrical shaped boss 35 which forms a shoulder 35a and screw threaded nipple 36. Passing through the bod-y 34 and axially throughthenipple 36 is a cylindrical passage 37, and at the end of the body opposite the nipple 36 is a shallow recess 38 which is covered by a screw cap 39. The body part 34 will be located Within the vacuum chamber 10, the shoulder 35a resting upon the bottom thereof and the-boss 35 projecting into the central aperture 11 so that the body part may be secured in' position by the nut 351). For convenience the body part 34 may be circular in cross section vand T shaped in vertical section so that by boring and counterboring another hole 40 a'zially parallel with the passage 37 internal4 lcommunication can be established between the chamber formed by the shallow recess 38 and the vacuum chamber 10. i

The bottom of the counterbored' portion of the hole 40 forms a leaky or imperfect seating fora ball etlwhich will be causedto rise from the seating by thesuction strokes of pistons of the engine thus permitting the air within the chamber 10 to be `partly exhausted butwill fall again onto the seating, thereby,-l closing the passage 40 and either maintaining f a partial vacuum in the chamber 10 .until air has leaked between the ball and its seating from the engine manifold intake through the piperlla, passage 37, chamber or lrecess 38 the passage 40 to the chamber 10 sufficiently to., destroyy the vacuum in the latter,.or until? it is again raised from the seating by the next suction stroke of any of the pistons of the engine which Vwould increase the vacuum. within the chamber-10. Any suitable pack-v ing may be used to form air tight joints between .thezscrew cap 39 and the body 34 and also between the body 34 and the chamber 10, and thedistance between the underside of the cap 39 and the bottom of the recess 38 should tested several other methods the appliance herein described and illustrated in the accompanying drawing has given the most perfect results. v

We claim a vacuum chamber connected by a pipe to the manifold intake of anV internal combustion engine, an escape valve adapted to temporarily maintaina `vacuum created within the chamber, said valve comprising a body ini cluding a chamber, `a removable4 cap closing the chamber, two passages through the body, both communicating with the chamber ofthe body, one' passage establishing communication between the pipe and body of thecham- A device of the classdescribed comprising KLJ- means for connecting the pipe to the body of the valve. f

In witness whereof we have signed this specification.

FREDERICK BERTRANDY WEST. KEVIN JOSEPH PIDCOCK. EDWIN DONKIN. 

